The invention relates generally to a variable width roll forming apparatus capable of forming a continuous web of sheet material as the web passes through a plurality of matching die rolls, and more particularly to a variable width roll forming apparatus which is capable of varying the spacing between matching die rolls, as well as compensating for variations in the width of the web.
Known roll forming machinery usually has a plurality of sets of roll dies, typically arranged in upper and lower matching pairs, and usually spaced apart along the length of the machine on roller stands. Typically, the roller dies at one stand will produce a continuous formation in the web, and the roller dies of the next stand will produce another formation, or for example increase the angle of the formation which has already been started at the previous stand and so on.
A wide variety of commercial and other products are made on such roll forming machines, such as roof decking siding, as well as a large number of components for consumer equipment. The shapes may simply be webs with edge formations formed along one edge or both, or may be C sections or U sections but in many cases consist of relatively complex formations with longitudinal formations being formed along the length of the web, side by side.
Generally speaking at each stand of rolls there are two lower dies and two upper dies arranged in pairs, on either side of a central web axis to form thereby various bends or shapes in the web. The lower dies engage the underside of the web and the upper dies engage the upper side of the web. The dies have circular shapes, and are mounted on rotatable axles so that the dies can rotate at the same speed as the sheet metal. A gear drive mechanism is coupled to the dies so as to drive them at the speed of the sheet metal.
Each set of such roller dies must be designed to provide a particular formation in the web. In addition, each pair of dies must have a clearance between them determined by the thickness of the web.
Thus, where it is desired to discontinue working on a web of one thickness, and to then run a web of another thickness through the dies, each pair of roller dies must be readjusted to a new clearance, to accommodate the new thickness of the new web. This has typically involved manual manipulation and costly down time in order to make these fine adjustments.
It would therefore be desirable to provide for automatic self-adjustment of the spacing or clearances between the pairs of dies in each stand. However, due to the shaping of the dies there are difficulties in such adjustments. Usually the dies will have two surfaces, one of the surfaces being more or less horizontal, or at least parallel to the plane of the web itself, and the other of the surfaces being at a web-forming angle.
Another set of problems arises if it is desired to use the same roller dies, to form a web having a width which is greater, or narrower than a preceding web.
In the past each of the stands situated on either side of the web would have to be manually moved further apart, or closer together, to take in to account the width of the new web to be processed. However, as will be readily appreciated, it was time consuming to dismantle the arrangement of dies for one web width, and then reassemble the dies with a greater or lesser number of rolls between them to suit the new web width. In addition, this was awkward and time-consuming manual work.
Commonly assigned U.S. application Ser. No. 09/394,309, filed on Sep. 10, 1999, now U.S. Pat. No. 6,282,932, and entitled xe2x80x9cRoll Forming Apparatus and Methodxe2x80x9d, discloses several embodiments of a roll forming machine that is capable of quickly adjusting the relative orientation between matching pairs of dies of a given roller stand to accommodate webs of differing gauges, as well as disclosing an automated procedure for moving groups of roller stands, on either side of the webbing, either farther apart or closer together, U.S. application Ser. No. 09/394,309, now U.S. Pat. No. 6,282,932, being herein incorporated by reference in its entirety.
As disclosed in U.S. application Ser. No. 09/394,309 and as illustrated in FIG. 1, the upper roll die 86 in a matching pair of roll dies, 86 and 82 respectively, is secured for rotation within an eccentric sleeve 90 so that rotation of the eccentric sleeve 90 will cause the upper die 86 to move in vertical relationship to its matching lower die 82. More particularly, a plurality of lower die drive shafts 80 are supported by suitable bearings directly in a side plate 38 of the roll forming machine. These drive shafts are driven by a suitable gear train and support lower forming dies 82. Telescoping driven shafts 84 extend from the drive shafts 80 to driven hubs (not shown) rotatably mounted in a matching side plates disposed on the opposing side of the webbing W, and driven shafts 84 extend completely through these driven hubs. The lower forming dies 82 are supported on such driven hubs. In this way the lower forming dies of all of stands in the roll forming machine are driven in unison.
A plurality of upper dies 86 are carried on upper shafts 88. The eccentric bearing sleeves 90 which carry the upper shafts 88 are both slidably and rotatably mounted in the side plate 38. The sleeves 90 define shaft openings 92 which are offset from the central axis of the sleeves 90 for reasons as described below. The upper die shafts 88 are themselves driven by a gear train connected to the lower shafts. As explained above, there is provided means for adjusting at least one of the upper and the lower dies, 86 and 82 respectively, relative to the other, so as to adjust the vertical clearance between the dies, to match the thickness or gauge of the web material W as closely as possible. Such adjustments may be made while the web W is actually running through the dies, thus compensating for variations in the thickness of the web along its length, all of which will be described below.
It will be seen that it is the upper dies 86 that are all adjustable relative to the lower dies 82, which are on fixed axes. However it will be appreciated that the lower dies 82 could be made adjustable while the upper dies 86 remain fixed, should such an architecture be desired.
As explained above each of the upper shaft sleeves 90 have eccentric shaft openings 92 for receiving die shafts 88 and the driven hubs (not shown) in the side plate 38. Each sleeve 90 is supported in a respective opening in the side plate 38.
The sleeves 90 are able to rotate in the side plate 38, in a manner to be described below, and thus cause upward and downward semi arcuate movement of upper die shafts 88 and their dies 86.
The sleeves 90 are also adjustable axially, i.e. horizontally, inwardly and outwardly, this produces what is in the end an adjustment of the upper dies 86 along diagonal axes relative to the web W to accommodate minor variations in the web thickness as it passes both through the horizontally opposed faces of each die pair, as well as through the angularly opposed faces of the die pair.
The mechanism by which this adjustment is achieved is also depicted in FIG. 1. Referring again to FIG. 1, each sleeve 90 is connected to a semi arcuate eccentric arm 60. Two bolts 62 pass through arcuate slots 64 in the arm 60 and are bolted into the sleeve 90. The eccentric arm 60 is formed with a pair of upwardly directed guides 66 which define a U shaped slot. An adjustment pin 68 is received in the U shaped slot of the guides 66. The pin 68 extends sideways from an adjustment or draw bar 61 which extends along the top of the side plate 38. The identical structure is provided for the opposite sleeve (not shown) which is mounted in the side plate on the opposing side of the web W. As would be appreciated, an identical draw bar will extend along the top of the non-illustrated matching side plate.
The pins 68 are located at spaced intervals along the draw bar 61 at spacings corresponding to the locations of the sleeves 90. A suitable power mechanism (not shown) at one end of bar 61 pushes or pulls it to provide the adjusting movement. As the bar 61 moves it will force the pin 68 located between the guides 66 to rotate the arm 60 through a small angular extent, an arc of one or two degrees in most cases being sufficient. This will in turn force the rotation of the sleeve 90 through the same arc. Since the sleeve 90 carries the die shaft 88 off center in an eccentric manner, the shaft 88 will swing upwardly or downwardly a fractional amount, which will be sufficient to adjust for the variations in thickness of the web.
This explains the vertical, transverse adjustment of the upper die 86 relative to the lower die 82.
A horizontal adjustment along the shaft axis is also provided by the mechanism depicted in FIG. 1. This is produced by a cam block 67 secured to the side plate 38 and the cooperating roller 63 which is bolted to the arm 60.
The block 67 is formed with a generally diagonal slot 65, which receives the roller 63. When the arm 60 is moved by the pin 68 so as to produce the small angular adjustment, it also causes the roller 63 to move along the slot 65. The axis of the slot 65 is angled along a diagonal axis so that the roller 63 must move along that angled axis. This will cause the arm 60 to move towards or away from the side plate 38. The sleeve 90 to which the arm 60 is attached will thus be forced to slide into or out of the plate 38. Again, the actual degree of movement is slight, but it is sufficient to produce the adjustment in die clearance required to accommodate variations in the web thickness.
Therefore, movement of the arm 60 caused by the roller 63 and the slot 65 will cause the guides 66 to slide outwardly or inwardly relative to the pin 68, but again the degree of movement will be slight. It will thus be seen that by this mechanism movement by the single draw bar 61 will cause simultaneous movement of the sleeve 90 both transverse to its axis and also axially along its axis, that is, both vertically and horizontally with respect to the lower die 82 and the side plate 38. These two degrees of movement will translate into movement of the upper die 86 along a diagonal axis relative to the lower die 82. The bolts 62 can be loosened, and the arm 60 can be adjusted by sliding the slots 64 relative to the bolts which can then be tightened once more. This enables the machine to be set up prior to operation to the optimum die clearance for a particular thickness of web. It will be readily appreciated that a more complete operational understanding of the mechanism depicted in FIG. 1 may be ascertained by a review of U.S. application Ser. No. 09/394,309 which, as discussed previously, has been incorporated by reference in its entirety.
As described above in conjunction with FIG. 1, changes in web thickness or gauge may be readily accommodated utilizing an eccentrically aligned upper (or lower) roll die in concert with a camming arrangement, while gross changes in the width of the web itself may be compensated for through the use of a drive mechanism which acts to shift one of the many opposing side plates either away or towards one another, as necessary, thereby selectively adjusting the width of specified portions of the roll forming apparatus.
It is important to note, however, that a roll forming apparatus as described above will typically be comprised of several, operationally integrated stations, or sets of die stands, which are housed within a matching plurality of respectively separate side plates on either side of the moving web. Such a configuration is necessary to enable differing stations of the roll forming apparatus to be arranged to accommodate a web of differing widths as the web travels the length of the roll forming apparatus. Thus, the roll forming apparatus typically requires a separate set of opposing side plates for a first station set at a first width, another set of opposing side plates for a second station set at a second width, yet another set of opposing side plates for a third station set at a third width, and so on, so as to accommodate the changing width of the web as it travels the length of the roll forming apparatus.
A major drawback, therefore, of the roll forming apparatus described above is that a single side plate on either side of the web typically cannot be employed, and as such, the rigidity and stability of the apparatus as a whole is lessened. Moreover, by stringing together separate stations of the roll forming apparatus, each with their own opposing pairs of side plates, the complexity of the alignment, as well as the complexity of the coordination, of these stations is greatly increased.
It is an object of the present invention to configure a roll forming apparatus which exhibits greater rigidity and stability.
It is another object of the present invention to configure a roll forming apparatus having a single pair of opposing side plates disposed along the entire length of the roll forming apparatus.
It is another object of the present invention to manipulate the separation width between selected pairs of die stands, exclusive of shifting the entirety of the opposing sides plates.
It is another object of the present invention to manipulate the separation width between selected pairs of die stands, exclusive of shifting the entirety of the opposing sides plates, while still maintaining the desired relationship between the upper and lower die pairs.
According to one embodiment of the present invention, a variable width roll forming apparatus for progressively forming a web of material directed therethrough includes a first side plate extending substantially an entire length of the roll forming apparatus and a second side plate extending substantially an entire length of the roll forming apparatus, the first side plate and the second side plate being oriented on opposing sides of an axis of movement of the web and substantially equidistant from one another. A plurality of roller die assemblies are disposed in apertures formed in the first side plate and the second side plate. An adjusting apparatus is utilized to selectively change a separation width between predetermined roller die assemblies in the first side plate and the second side plate, wherein the roll forming apparatus defines at least two differing widths between roller die assemblies disposed in the first side plate and the second side plate while maintaining the substantially equidistant spacing between the first side plate and the second side plate.
These and other objectives of the present invention, and their preferred embodiments, shall become clear by consideration of the specification, claims and drawings taken as a whole.